Why are some vaccines given as a single dose and others as multiple doses?
A. Vaccines may be given multiple times for a few reasons. First, some vaccines are given more than once so that a greater number of people can be protected against the disease. For example, when adults get the chickenpox vaccine, 78 of 100 will be protected after one dose, but that number rises to 99 of 100 after the second dose. Since the additional dose is not harmful and provides extra protection even in first-dose responders, everyone is recommended to get the second dose. Second, some vaccines provide a low level of protection after a single dose, but additional doses provide a greater response, so that individuals are better protected. This is true of the vaccine for Haemophilus infleunzae type b or Hib. Another reason for multiple doses is that immune responses last longer after more than one dose of some vaccines. The pertussis vaccine is an example of this. Finally, some vaccines protect against agents that change often enough that older versions would not offer protection. T
Vaccines may be given multiple times for a few reasons. First, some vaccines are given more than once so that a greater number of people can be protected against the disease. For example, when adults get the chickenpox vaccine, 78 of 100 will be protected after one dose, but that number rises to 99 of 100 after the second dose. Since the additional dose is not harmful and provides extra protection even in first-dose responders, everyone is recommended to get the second dose. Second, some vaccines provide a low level of protection after a single dose, but additional doses provide a greater response, so that individuals are better protected. This is true of the vaccine for Haemophilus infleunzae type b or Hib. Another reason for multiple doses is that immune responses last longer after more than one dose of some vaccines. The pertussis vaccine is an example of this. Finally, some vaccines protect against agents that change often enough that older versions would not offer protection. The
Related Questions
- What if during that given time frame, my child received more than one dose of the same vaccine - how many doses will need to be repeated?
- If a child received two doses of Hib vaccine and the second dose was given at 13 months of age, does the child need a third dose?
- Why are some vaccines given as a single dose and others as multiple doses?
